Normalize direction vector after reflecting particle. Closes #192.
Set blank default for xs listing alias.
Merge branch 'master' into cmfd_clean
removed cmfd message passing and re-made dependencies
got rid of 2 group fixed data
changed comments and updated some parts of code
cleaned up comments and some bits of code
cleaned up cmfd input comments and bits of code
no longer need cmfd message passing routines
cleaned up comments in cmfd output
removed some useless cmfd vars and removed use mpi from global